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191.
Adel Alahmadi Husain Alhazmi Shakir Ali Tor Helleseth Rola Hijazi Chunlei Li Patrick Solé 《系统科学与复杂性》2017,30(4):950-966
This paper constructs a cyclic ?4-code with a parity-check matrix similar to that of Goethals code but in length 2m + 1, for all m ≥ 4. This code is a subcode of the lifted Zetterberg code for m even. Its minimum Lee weight is shown to be at least 10, in general, and exactly 12 in lengths 33, 65. The authors give an algebraic decoding algorithm which corrects five errors in these lengths for m = 5, 6 and four errors for m > 6. 相似文献
192.
Syed Zahid Ali Shah Tariq Hussain Deming Zhao Lifeng Yang 《Cellular and molecular life sciences : CMLS》2017,74(6):1061-1074
Accumulation of misfolded/unfolded aggregated proteins in the brain is a hallmark of many neurodegenerative diseases affecting humans and animals. Dysregulation of calcium (Ca2+) and disruption of fast axonal transport (FAT) are early pathological events that lead to loss of synaptic integrity and axonal degeneration in early stages of neurodegenerative diseases. Dysregulated Ca2+ in the brain is triggered by accumulation of misfolded/unfolded aggregated proteins in the endoplasmic reticulum (ER), a major Ca2+ storing organelle, ultimately leading to neuronal dysfunction and apoptosis. Calcineurin (CaN), a Ca2+/calmodulin-dependent serine/threonine phosphatase, has been implicated in T cells activation through the induction of nuclear factor of activated T cells (NFAT). In addition to the involvement of several other signaling cascades, CaN has been shown to play a role in early synaptic dysfunction and neuronal death. Therefore, inhibiting hyperactivated CaN in early stages of disease might be a promising therapeutic strategy for treating patients with protein misfolding diseases. In this review, we briefly summarize the structure of CaN, inhibition mechanisms by which immunosuppressants inhibit CaN, role of CaN in maintaining neuronal and synaptic integrity and homeostasis and the role played by CaN in protein unfolding/misfolding neurodegenerative diseases. 相似文献
193.
Platoon formation of highway vehicles is a critical foundation for autonomous or semiautonomous vehicle control for enhanced safety,improved highway utility,increased fuel economy,and reduced emission toward intelligent transportation systems.Platoon control encounters great challenges from vehicle control,communications,team coordination,and uncertainties.This paper introduces a new method for coordinated control of platoons by using integrated network consensus decisions and vehicle control.To achieve suitable coordination of the team vehicles based on terrain and environmental conditions,the emerging technology of network consensus control is modified to a weighted and constrained consensus-seeking framework.Algorithms are introduced and their convergence properties are established.The methodology employs neighborhood information through on-board sensors and V2 V or V2 I communications,but achieves global coordination of the entire platoon.The ability of the methods in terms of robustness,disturbance rejection,noise attenuation,and cyber-physical interaction is analyzed and demonstrated with simulated case studies. 相似文献
194.
Marjan Radi Behnam Dezfouli Kamalrulnizam Abu Bakar Shukor Abd Razak Mohammad Ali Nematbakhsh 《清华大学学报》2011,16(5):475-490
The existing multipath routing protocols for wireless sensor networks demonstrate the efficacy of traffic distribution over multiple paths to fulfill the Quality of Service (QoS) requirements of different applications.However,the performance of these protocols is highly affected by the characteristics of the wireless channel and may be even inferior to the performance of single-path approaches.Specifically,when multiple adjacent paths are being used concurrently,the broadcast nature of wireless channels res... 相似文献
195.
柿产业存在的问题及发展对策 总被引:1,自引:0,他引:1
柿树是我国主栽果树种类之一,栽培历史悠久.从柿子品种资源丰富,栽培管理容易,市场需求大和产品品种多样等方面分析了我国发展柿产业的优势.通过对我国柿树生产、保鲜加工技术和营销方面所存在问题的研究,提出发展柿产业相应的对策:1)调整品种结构,培育和引进优良品种,普及栽培技术;2)加强柿贮藏保鲜和加工技术的研究;3)合理布局,发挥地域优势,发展特色产业链;4)建立服务体系,完善营销渠道. 相似文献
196.
Sajjad Hussain Yaqoob Khan Volodymyr Khranovskyy Riaz Muhamm Rositza Yakimova 《自然科学进展(英文版)》2013,23(1):44-50
Atmospheric pressure MOCVD was used to deposit ZnO layers on sapphire and homoepitaxial template under different oxygen flow rates.Oxygen content affects the lattice constant value and texture coefficient of the films as evidenced by the θ-2θ peaks position and their intensity.Films deposited at lower oxygen flow rate possess higher value of strain and stresses.ZnO films deposited at high oxygen flow rates show intense UV emissions while samples prepared under oxygen deficient conditions exhibited defect related emission along with UV luminescence.The results are compared to the ZnO films deposited homoepitaxially on annealed ZnO samples.The data obtained suggest that ZnO stoichiometry is responsible for the structural and optical quality of ZnO films. 相似文献
197.
Ahmat Ali Ruxangul Jamal Weiwei shao Adalet Rahman Yakupjan Osman Tursun Abdiryim 《自然科学进展(英文版)》2013,23(6):524-531
Poly(3,4-propylenedioxythiophene)/nano-Zinic Oxide(PProDOT/ZnO) composites with the content of 3-7 wt%nano-ZnO were synthesized by the solid-state method with FeCl3 as oxidant.The structure and morphology of the composites were characterized by Fourier transform infrared(FTIR)spectroscopy,ultraviolet-visible(UV-vis) absorption spectroscopy,X-ray diffraction(XRD) and transmission electron microscopy(TEM).The electrochemical performances of the composites were investigated by galvanostatic charge-discharge,cyclic voltammetry and electrochemical impedance spectroscopy(EIS).The photocatalytic activities of the composites were investigated by the degradation of methylene blue(MB) dyes in aqueous medium under UV light irradiation.The results from FTIR and UV-vis spectra showed that the PProDOT/ZnO composites were successfully synthesized by solid-state method,and nano-ZnO had great influences on the conjugation length and oxidation degree of the polymers.Furthermore,the PProDOT/5 wt%ZnO had the highest conjugation and oxidation degree among the composites.The results of XRD analysis indicated that there were some FeCl4- ions as doping agent in the PProDOT matrix,and the content of ZnO had no effect on diffraction pattern of PProDOT.Morphological studies revealed that the pure PProDOT and composites had similar morphological structure,and all the composites displayed an irregular sponge like morphology.The results of electrochemical tests showed that the PProDOT/5 wt%ZnO had a higher electrochemical activity with a specific capacitance value of 220 F g-1 than others.The results from photocatalytic activities of the composites indicated that the PProDOT/5 wt%ZnO had better photocatalytic activity than other composites. 相似文献
198.
Crow YJ Leitch A Hayward BE Garner A Parmar R Griffith E Ali M Semple C Aicardi J Babul-Hirji R Baumann C Baxter P Bertini E Chandler KE Chitayat D Cau D Déry C Fazzi E Goizet C King MD Klepper J Lacombe D Lanzi G Lyall H Martínez-Frías ML Mathieu M McKeown C Monier A Oade Y Quarrell OW Rittey CD Rogers RC Sanchis A Stephenson JB Tacke U Till M Tolmie JL Tomlin P Voit T Weschke B Woods CG Lebon P Bonthron DT Ponting CP Jackson AP 《Nature genetics》2006,38(8):910-916
Aicardi-Goutières syndrome (AGS) is an autosomal recessive neurological disorder, the clinical and immunological features of which parallel those of congenital viral infection. Here we define the composition of the human ribonuclease H2 enzyme complex and show that AGS can result from mutations in the genes encoding any one of its three subunits. Our findings demonstrate a role for ribonuclease H in human neurological disease and suggest an unanticipated relationship between ribonuclease H2 and the antiviral immune response that warrants further investigation. 相似文献
199.
James M.TIEN Ananth KRISHNAMURTHY Ali YASAR Department of Decision Sciences Engineering Systems Rensselaer Polytechnic Institute Eighth St.Troy New York USA 《系统科学与系统工程学报(英文版)》2004,13(3):257-278
Our focus herein is on developing an effective taxonomy for the simultaneous and real-timemanagement of supply and demand chains.More specifically,the taxonomy is developed in terms ofits underpinning components and its research foci.From a components perspective,we first considerthe value chain of supplier,manufacturer,assembler,retailer,and customer,and then develop aconsistent set of definitions for supply and demand chains based on the location of the customer orderpenetration point.From a research perspective,we classify the methods that are employed in themanagement of these chains,based on whether supply and/or demand are flexible or fixed.Interestingly,our taxonomy highlights a very critical research area at which both supply and demandare flexible,thus manageable.Simultaneous management of supply and demand chains sets the stagefor mass customization which is concerned with meeting the needs of an individualized customermarket.Simultaneous and real-time management of supply and demand chains set 相似文献
200.